Describe the cross section

Answer:
D. Square
Step-by-step explanation:
A cross section is the shape that we get when we cut the object.
Here the given object is a cube.
It is cut straight through the middle.
Imagine a cube cut through the middle, when we look at the same on the top, we get square.
Since in a cube all the sides are equal.
Therefore, we get square when we cut the cube straight through the middle.
Answer: D. Square.